The invention concerns a packing for animal feed.
For the feeding of animals, especially aquatic animals, in aquaria, there can, in principle, be used living feed, freeze-dried natural feed, frozen feed and dried feed. In the form of frozen feed, to warm and cold water ornamental fish in fresh and sea water aquaria are fed e.g. saline crayfish, krill, water fleas, stream flea crayfish, sludge tube worms, red and white gnat larvae, zooplankton, fish roes or calf heart. Specialised aquariarists often exclusively use living feed, freeze-dried natural feed and/or frozen feed. However, the preponderant majority of aquariarists administer dried feed, thus flakes, extrudates, tablets or pellets, in part in combination with the other types of feed. As packing for dried feed, there are, above all, used comparatively small containers of glass or synthetic material with reclosable lid.
From WO 99/12430 is known a feed for aquatic animals which is present in the form of a viscous gel. The gel-like feed is especially suitable for warm and cold water ornamental fish in the aquarium and can be used as replacement for frozen feed. However, in the case of this feed, the problem exists of an extreme susceptibility to microbiological decomposition. The feed consists of about 82% water, the remainder are predominantly protein carriers which can be microbiologically burdened. Therefore, for the preservation, there comes into question a pasteurisation process only in combination with preserving materials. However, the usual preserving agents show a very negative influence on the eating behaviour, especially of fish (poor acceptance). In addition, many of the preserving agents are only effective in acid medium, whereby the product smell is falsified which again leads, to a poor acceptance.
The containers of glass or synthetic material known as packing for dried feed come into question as packing for the gel-like feed described in WO 99/12430 just as little as, for example, heat-sterilisable portion packings of aluminium foil as find use e.g. for milk or marmalade. These packings have proved to be unsuitable in the case of use as animal feed packing. Disadvantageous in these packings is, inter alia, that the feed must be removed with a spoon since a portioning of the feed without further aids is not possible. The feed removal in this way proves to be of little attractiveness for fish since in water it rapidly sinks to the bottom.
The use of packings of special foils, as are known for mustard and ketchup portion packings, would be conceivable. However, with regard to the use as packing for animal feed, these foils display several disadvantages. On the one hand, they possess a very poor opening behaviour in the case of tearing open by hand, on the other hand the said packings are not heat-sterilisable, as well as only limitedly impermeable for oxygen. However, sterilisability by heat is an indispensable prerequisite for animal feed packings when a sufficient keeping of the feed is to be achieved. A minimum keeping of e.g. two years, is not achievable by a pasteurisation process alone.
A sterilisation process with avoidance of microbiologically effective preservation agents shows, in comparison with a pasteurisation process, the advantage of a better acceptance of the feed by the animals, a shortening of the processing time necessary for the preservation and the ensuring of a minimum keeping of two years.
Furthermore, suitable animal feed packings must display a high oxygen impermeability, as well as light impermeability. This is necessary because the fats contained in the animal feed are oxidised by oxygen which leads to rancidity, whereas vitamins of the animal feed are decomposed by the incidence of light. However, materials with a sufficient impermeability for oxygen display an increasingly poor flexibility. These packings can thereby not be satisfactorily pressed out, which represents a disadvantage especially in the case of the portioning of small amounts of feed.
As a further requirement for animal feed packings is to be mentioned a smallest possible-water permeability of the packing. A drying out of the feed is thereby prevented.
A packing for animal feed, especially aquatic animal feed, is to be provided which, besides a sufficient storability, also ensures an easy handling and portioning of the feed. According to the invention, this task is solved by the packing for animal feed according to independent patent claim 1, the process according to independent patent claim 7 and the use according to independent claim 9.
The packing for animal feed according to the invention consists of a foil which is produced by lamination of three different foils. By xe2x80x9claminationxe2x80x9d is generally to be understood the pressing together or rolling of two or more foil strips to give a multi-layer, thicker foil strip. The placing together of the foils can thereby take place by temperature increasing in the case of the pressing or rolling and/or by addition of adhesive.
The packing according to the invention consists of a three-layered foil, namely, of a foil consisting of chlorinated polypropylene (Cpp), of an aluminium. foil and of a foil of polyethylene terephthalate (PETP). These 3 foils are connected by the above-described xe2x80x9claminatingxe2x80x9d to give a three-layered foil, whereby the aluminium foil stands in contact with the other two foils, thus the aluminium foil forms the middle layer. In the following, for the sake of simplicity, this three-layered foil is designated as an aluminium foil coated on both sides. Thus, this aluminium foil is coated on the side standing in contact with the animal feed with chlorinated polypropylene (Cpp) and on the opposite-lying side with polyethylene terephthalate (PETP).
The thickness of the three-layered foil amounts to between 20 and 200 xcexcm, whereby the coating with polyethylene terephthalate has a thickness between 4 and 40 xcexcm, the aluminium foil a thickness between 3 and 30 xcexcm and the coating with chlorinated polypropylene a thickness between 13 and 130 xcexcm. A foil is preferred with a thickness between 40 and 100 xcexcm, especially between 52 and 70 xcexcm, whereby the coating with polyethylene terephthalate has a thickness between 8 and 20 xcexcm, especially between 10 and 14 xcexcm, the aluminium foil a thickness between 6 and 15 xcexcm, especially between 7 and 11 xcexcm and the coating with chlorinated polypropylene a thickness between 26 and 65 xcexcm, especially between 35 and 45 xcexcm. Quite espesially preferred is a foil, the thickness of which amounts to about 61 xcexcm, whereby the coating with polyethylene terephthalate has a thickness of about 12 xcexcm, the aluminium foil a thickness of about 9 xcexcm and the coating with chlorinated polypropylene a thickness of about 40 xcexcm.
The described foil can be heat-sterilised, displays a sufficient impermeability for oxygen and possesses a sufficient flexibility. Due to the outstanding suitability of the foils for sterilisation by heat, as well as the excellent properties as oxygen barrier, the storage stability of gel-like feed according to WO 99/12430 of two years is achieved. This excellent keeping is achieved in spite of the omission of microbiologically-effective preservation agents, such as calcium propionate, potassium sorbate, citric acid, lactic acid, common salt or sea salt. The good flexibility of the foil ensures an easy ability to be pressed out and thus simple portionability of the feed also in the case of a small feed portion per packing of between 1 and 15 g, thus especially of small amounts, such as 2 to 4 g. The packing content can be divided up into still smaller portions due to the easy ability to be pressed out.
Especially having regard to the portionability but also, quite generally, for the simplified handling, the packing according to the invention-can find use in a special external form. A piece of the three-layered foil, shaped as desired, is, for this purpose, bent uniformly through 180xc2x0 so that two sides coated with Cpp come to lie on one another. The bending does not take place with especial intensity since no kink may arise in the foil, on the contrary a hollow space is to be formed which serves for the reception of the animal feed. This hollow space is closed in its outer region by heat sealing, thus by pressing at elevated temperature, of the two foil layers.
According to the invention, the hollow space has a bottle neck-like extension. The heat-sealed part of the foil is so perforated that, in the case of opening by hand, an opening is formed transversely to the bottle neck-like extension. The three-layered foil can be exactly separated off along the perforated indentation by hand with two parallel tear-off edges and thereby forms an opening in the hollow space which is so dimensioned that a thin, worm-shaped feed strand can be pressed out.
The advantage of this manner of portioning of the animal feed is especially clear when the feed is used for aquatic animals in fresh and sea water, especially fish, shrimps and other invertebrates. If the feed is to be made available not only for surface fish and for fish of the middle zones as well as for bottom fish and other bottom-living forms of life, then the feed must, namely, float long enough on the top in order to allow the surface fish to become satisfied, it must float long enough in the water in order to satisfy fish of the middle zones and it must sink in compact state at the right speed in order to be fully taken up by bottom fish.
The above-described worm-shaped feed strand displays precisely these properties. Beside the fact that, on the basis of its properties, it remains stable and does not dissolve immediately, in addition it sinks only relatively slowly and, in this way, possesses sufficient attractiveness for all aquarium inhabitants. Besides the density of the aquatic animal feed, for these properties the cross-section in the direction of sinking of the feed portion also naturally also plays a decisive part. A slow sinking can then only be achieved when the feed portion has a relatively large cross-section in the direction of sinking since the flow buoyancy then counters sufficiently. An optimum relationship is achieved by the pressing out from the bottle neck-like elongation of the hollow space of the packing according to the invention.
Various forms of application are realisable with the bottle neck-like elongation. Worm-shaped pieces of any desired length can be allowed to fall on the water surface. These pieces then sink to the bottom. By careful dosing, short worm-shaped pieces float for a comparatively long time on the water surface. A direct feeding of individual fish is possible in that one holds the bottle neck-like elongation under the water and doses the feed to the fish directly into the mouth.
In principle, the packing according to the invention can be used for all animal feed products, the storability of which can be prolonged by sterilisation. However, the main point of the present invention lies in an animal feed packing for aquatic animals in fresh and sea water, especially fish, shrimps and other invertebrates.